我正在實現一個名爲MyAdapter的類,它擴展了BaseAdapter。在類myAdapter中,我實現了一個名爲AttemptLike的類,它擴展了AsyncTask。在類AttemptLike while Implementind doInBackground函數中,我無法使用finish();所以當我調用類似嘗試類時,我的應用每次都會崩潰。所以請告訴我如何處理錯誤。完成()不在AsyncTask中執行
的代碼是這樣
class MyAdapter extends BaseAdapter{
.
.
.
public class Attemptlike extends AsyncTask<String, String, String>{
{
protected String doInBackground(String... args)
{
try
{
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("somedata1", field1));
params.add(new BasicNameValuePair("somedata2", field2));
params.add(new BasicNameValuePair("geteventdata", evnt));
Log.d("request!", "starting");
JSONObject json = jsonParser.makeHttpRequest(LOGIN_URL, "POST", params);
// checking log for json response
Log.d("Login attempt", json.toString());
// success tag for json
success = json.getInt(TAG_SUCCESS);
if (success == 1)
{
Log.d("Successfully Liked!", json.toString());
finish();
// this finish() method is what i am not able use which is resulting in crashing of app
}
catch (JSONException e)
{
e.printStackTrace();
}
return null;
}
}
new AttemptLogin().execute();
return convertView;
}
}
堆棧跟蹤
FATAL EXCEPTION: AsyncTask #1
Process: ks.developers.festo, PID: 29568
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:304)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String org.json.JSONObject.toString()' on a null object reference
at ks.developers.festo.list.adapter.MyAdapter$2$1AttemptLike.doInBackground(MyAdapter.java:237)
at ks.developers.festo.list.adapter.MyAdapter$2$1AttemptLike.doInBackground(MyAdapter.java:1)
at android.os.AsyncTask$2.call(AsyncTask.java:292)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
... 4 more
'finish()'不是'AsyncTask'或者'BaseAdapter'的方法。你想做什麼? –
完成是針對活動的,因此如果您想關閉asynctask中的調用活動,請選中[此答案](http://stackoverflow.com/a/12170947/562840)。 – Mikel
我在這裏粘貼堆棧跟蹤只是看看它。 – Karrthik